This invention relates to a human lumbar model structure for simulating a pressure applied to nucleus pulposus in a human lumbar and an application equipment utilizing the structure. More particularly, this invention relates to a human lumbar model structure capable of objectively and quantitatively estimating and evaluating a ride vibration comfort which would be felt by a human being (an occupant, a driver, a passenger, etc.) on a vehicle such as a motor vehicle, a train, a vessel, and a spacecraft travelling with vibration, variation in speed, and/or change of acceleration.
Motor vehicles are typical vehicles which have widely spread in recent years and are continuously and infinitely developing in the modern society. As a consequence, different types of motor vehicles have been used in various uses, respectively. There are various models or classes in motor vehicles of one type of use (for example, passenger cars). On the other hand, many people have came to pay attention to safety and the ride vibration comfort of vehicles upon purchasing their vehicles.
For safety, motor vehicles for each of types of uses have been ranked through various kinds of collision or crash tests, the analysis of damages in those motor vehicles involved in accidents, and so on. On the other hand, evaluation of motor vehicles in the above-mentioned ride vibration comfort relies upon sensory tests in which test results widely fluctuate among individuals. Thus, no basis for objective or quantitative evaluation has been established yet.
Long-distance or long-time drivers often suffer from herniation of a lumbar intervertebral disk. According to one of the most convincing theories accepted by many orthopedists, the occurrence and the aggravation of the above-mentioned hernia are correlated with ride vibration comfort when travelling in motor vehicles.
In view of the above, it is required to realize a human lumbar model structure and application equipment utilizing the structure in order to objectively and quantitatively evaluate ride vibration comfort.